Dear Sir or Madam

I am writing to enquire about …

I am writing to request further information about …

I am writing in response to your advertisement / offer.

I saw your advertisement on your website / in the newspaper / last week.

With reference to your advertisement

Further to ...

First of all..

I would like to know whether …

In addition,

Could you please inform me about …

Moreover,

I would be grateful if you could let me know …

Finally, 

I would appreciate some further details regarding …

Thank you very much in advance for your help.

I look forward to your early reply.

I look forward to hearing from you.

Yours sincerely, (nom connu)

Yours faithfully, (Sir or Madam)

Dear Ms ..

Thank you for your email regarding …

Thank you for contacting us about …

We have received your request concerning …

We are pleased to inform you that …

We would be happy to confirm that …

Your request has been approved.

We can confirm that this will be possible.

Unfortunately, we are unable to …

We regret to inform you that this will not be possible.

Due to current circumstances, we cannot …

This request cannot be fulfilled at this time.

However, we would like to suggest …

As an alternative, we can offer …

We would be happy to propose another solution.

Please find below the requested information.

The check-in time is … and the check-out time is …

Housekeeping is included / not included.

Pets are allowed / not allowed under certain conditions.

Should you require any further information, please do not hesitate to contact us.

We remain at your disposal for any additional questions.

We look forward to welcoming you.

Yours sincerely,

I am writing to complain about …

I am writing regarding a problem I experienced with …

I wish to express my dissatisfaction with …

Unfortunately, the service did not meet my expectations.

There were several issues during my stay / experience.

The main problem was that …

First of all, …

In addition, …

Moreover, …

The room was not clean when we arrived.

The product was damaged / faulty / not working properly.

The service was delayed by several hours.

Despite my previous request, the problem was not solved.

As a result, I was extremely disappointed.

This caused significant inconvenience.

This situation affected my stay / my trip / my experience.

I was unable to fully enjoy …

I would like to request a refund / compensation.

I would appreciate a replacement or a full refund.

I kindly ask you to take the necessary measures to resolve this issue.

I expect an explanation and an appropriate solution.

• I hope this matter will be resolved as soon as possible.
• Thank you for your attention to this matter.
• I look forward to your reply.